Is it just me or are there not enough barb villages? I have a complete shortage of iron too. I'll get a couple hundred of timber and clay and only get around 20 iron.
personally, I think there are too many barbarian villages, the only complaint I have is that they're over farmed in my area and not growing, so I'm having to send my cavalry farther away to greener pastures, but that's just part of the game also, lol.
Don't worry though, when protection ends plenty of farms will open up to us. ;>